Best blog post I've read in a long time (and I read a lot!): Chris Dillow's Experts and the Demand for Certainty.
It's a sharp, spot-on, well-reasoned, well-written analysis, and -- it finally explains to me why I've always gotten so much push-back when, as an expert in my field (software development, and the management thereof), I offer "customers" my forecasts in the right form.
By "customers", here, I mean stakeholders of any stripe, including most product managers, top managers, etc -- even other developers, when they look up to me as a manager, mentor, or "senior advisor" figure rather than sensibly interacting with me as a peer!
And, the right form of forecast is always going to be expressed something like "X plus or minus Y" (or equivalently "between Z and T", where Z=X-Y and T=X+Y), accurately and explicitly expressing the margin of error that always accompanies any prediction (you can take the "with 95% probability" proviso as implied in any such quantitative expression).
Here's why I invariably get vehement push-back against expressing forecasts in the only sensible ways: the "customers" don't want from me, the expert, my knowledge; rather, what they want is certainty -- fake, bogus, fraudulent certainty is so much better than the messy, error-margin-involving business that's inevitable when you reach towards knowledge of reality:-(.
Now, this important realization doesn't teach me how to force stakeholders to face reality, but it does help me frame and understand their mindset, and thus helps me predict (with some margin of error, to be sure;-) how well or badly various communication strategies will work...